Add `partitions_scanned` and `partitions_total` to Statistics

[BohuTANG]

After #3903 checked in, we should add partitions_scanned and partitions_total to Statistics https://github.com/datafuselabs/databend/blob/d8cf752e80afc98ff173c38a2af4488601cc7cc8/common/planners/src/plan_statistics.rs#L16 and show them in the explain:

https://github.com/datafuselabs/databend/blob/d8cf752e80afc98ff173c38a2af4488601cc7cc8/common/planners/src/plan_display_indent.rs#L207-L213

[BohuTANG]

Let me take